MICROPROCESSOR:

1. Which interrupt has the highest priority? a) INTR b) TRAP c) RST6.5 2. In 8085 name the 16 bit registers?

a) Stack pointer b) Program counter c) a & b 3. Which of the following is hardware interrupts?

a) RST5.5, RST6.5, RST7.5 b) INTR, TRAP c) a & b 4. What is the RST for the TRAP?

a) RST5.5 b) RST4.5 c) RST4 5. What are level Triggering interrupts?

a) INTR&TRAP b)RST6.5&RST5.5 c)RST7.5&RST6.5 6. Which interrupt is not level sensitive in 8085?

a) RST6.5 is a raising edge-trigging interrupt. b) RST7.5 is a raising edge-trigging interrupt. c) a & b. 7. What are software interrupts?

a) RST 0 - 7 b) RST 5.5 - 7.5 c) INTR, TRAP 8. Which stack is used in 8085?

a) FIFO b) LIFO c) FILO 9. Why 8085 processor is called an 8 bit processor?

a) Because 8085 processor has 8 bit ALU. b) Because 8085 processor has 8 bit data bus. c) a & b. 10. What is SIM?

a) Select Interrupt Mask b) Sorting Interrupt Mask c) Set Interrupt Mask. 11. RIM is used to check whether, ______

a) The write operation is done or not b) The interrupt is Masked or not c) a & b 12. What is meant by Maskable interrupts?

a) An interrupt which can never be turned off. b) An interrupt that can be turned off by the programmer. c) none 13. In 8086, Example for Non maskable interrupts are

a) Trapb) RST6.5 c) INTR 14. What does microprocessor speed depends on?

a) Clock b) Data bus width c) Address bus width 15. Can ROM be used as stack?

a) Yes b) No c) sometimes yes, sometimes no 16. Which processor structure is pipelined?

a) all x80 processors b) all x85 processors c) all x86 processors 17. Address line for RST3 is?

a) 0020H b) 0028H c) 0018H 18. In 8086 the overflow flag is set when

a) The sum is more than 16 bits b) Signed numbers go out of their range after an arithmetic operation c) Carry and sign flags are set d) During subtraction 19. The advantage of memory mapped I/O over I/O mapped I/O is,

a) Faster b) Many instructions supporting memory mapped I/O c) Require a bigger address decoder d) All the above 20. BHE of 8086 microprocessor signal is used to interface the

a) Even bank memory b) Odd bank memory c) I/O d) DMA 21. In 8086 microprocessor the following has the highest priority among all type interrupts.

a) NMI b) DIV 0 c) TYPE 255 d) OVER FLOW 22. In 8086 microprocessor one of the following statements is not true.

a) Coprocessor is interfaced in MAX mode b) Coprocessor is interfaced in MIN mode c) I/O can be interfaced in MAX / MIN mode d) Supports pipelining 23. 8088 microprocessor differs with 8086 microprocessor in

a) Data width on the output b) Address capability c) Support of coprocessor

d) Support of MAX / MIN mode 24. Address line for TRAP is?

a) 0023H b) 0024H c) 0033H Key: 1.1 C 1.2 C 1.3 C 1.4 B 1.5 B 1.6 B 1.7 A 1.8 B 1.9 A 1.10 C 1.11 B 1.12 B 1.13 A 1.14 C 1.15 B 1.16 C 1.17 C 1.18 B 1.19 D 1.20 B 1.21 A 1.22 B 1.23 A 1.24 B

8085 microprocessor questions

1. What are the various registers in 8085? - Accumulator register, Temporary register, Instruction register, Stack Pointer, Program Counter are the various registers in 8085 .

2. In 8085 name the 16 bit registers? - Stack pointer and Program counter all have 16 bits.

3. What are the various flags used in 8085? - Sign flag, Zero flag, Auxillary flag, Parity flag, Carry flag.

4. What is Stack Pointer? - Stack pointer is a special purpose 16-bit register in the Microprocessor, which holds the address of the top of the stack.

5. What is Program counter? - Program counter holds the address of either the first byte of the next instruction to be fetched for execution or the address of the next byte of a multi byte instruction, which has not been completely fetched. In both the cases it gets incremented automatically one by one as the instruction bytes get fetched. Also Program register keeps the address of the next instruction.

6. Which Stack is used in 8085? - LIFO (Last In First Out) stack is used in 8085.In this type of Stack the last stored information can be retrieved first.

7. What happens when HLT instruction is executed in processor? - The Micro Processor enters into Halt-State and the buses are tri-stated.

8. What is meant by a bus? - A bus is a group of conducting lines that carriers data, address, & control signals.

9. What is Tri-state logic? - Three Logic Levels are used and they are High, Low, High impedance state. The high and low are normal logic levels & high impedance state is electrical open circuit conditions. Tri-state logic has a third line called enable line.

10. Give an example of one address microprocessor? - 8085 is a one address microprocessor.

11. In what way interrupts are classified in 8085? - In 8085 the interrupts are classified as Hardware and Software interrupts.

12. What are Hardware interrupts? - TRAP, RST7.5, RST6.5, RST5.5, INTR.

13. What are Software interrupts? - RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7.

14. Which interrupt has the highest priority? - TRAP has the highest priority.

15. Name 5 different addressing modes? - Immediate, Direct, Register, Register indirect, Implied addressing modes.

16. How many interrupts are there in 8085? - There are 12 interrupts in 8085.

17. What is clock frequency for 8085? - 3 MHz is the maximum clock frequency for 8085.

18. What is the RST for the TRAP? - RST 4.5 is called as TRAP.

19. In 8085 which is called as High order / Low order Register? - Flag is called as Low order register & Accumulator is called as High order Register.

20. What are input & output devices? - Keyboards, Floppy disk are the examples of input devices. Printer, LED / LCD display, CRT Monitor are the examples of output devices.

21. Can an RC circuit be used as clock source for 8085? - Yes, it can be used, if an accurate clock frequency is not required. Also, the component cost is low compared to LC or Crystal.

22. Why crystal is a preferred clock source? - Because of high stability, large Q (Quality Factor) & the frequency that doesn’t drift with aging. Crystal is used as a clock source most of the times.

23. Which interrupt is not level-sensitive in 8085? - RST 7.5 is a raising edge-triggering interrupt.

24. What does Quality factor mean? - The Quality factor is also defined, as Q. So it is a number, which reflects the lossness of a circuit. Higher the Q, the lower are the losses.

25. What are level-triggering interrupt? - RST 6.5 & RST 5.5 are level-triggering interrupts.

Interview Questions Answers (Set - 1)What is a Microprocessor?Microprocessor is a program-controlled device, which fetches the instructions from memory, decodes and executes the instructions. Most Micro Processor are single- chip devices.

What are the flags in 8086?In 8086 Carry flag, Parity flag, Auxiliary carry flag, Zero flag, Overflow flag, Trace flag, Interrupt flag, Direction flag, and Sign flag.

Why crystal is a preferred clock source?Because of high stability, large Q (Quality Factor) & the frequency that doesn?t drift with aging. Crystal is used as a clock source most of the times.

In 8085 which is called as High order / Low order Register?Flag is called as Low order register & Accumulator is called as High order Register.

What is Tri-state logic?Three Logic Levels are used and they are High, Low, High impedance state. The high and low are normal logic levels & high impedance state is electrical open circuit conditions. Tri-state logic has a third line called enable line.

What happens when HLT instruction is executed in processor?The Micro Processor enters into Halt-State and the buses are tri-stated.

Which Stack is used in 8085?LIFO (Last In First Out) stack is used in 8085.In this type of Stack the last stored information can be retrieved first

What is Program counter?Program counter holds the address of either the first byte of the next instruction to be fetched for execution or the address of the next byte of a multi byte instruction, which has not been completely fetched. In both the cases it gets incremented automatically one by one as the instruction bytes get fetched. Also Program register keeps the address of the next instruction.

What are the various registers in 8085?Accumulator register, Temporary register, Instruction register, Stack Pointer, Program Counter are the various registers in 8085

What is 1st / 2nd / 3rd / 4th generation processor?The processor made of PMOS / NMOS / HMOS / HCMOS technology is called 1st / 2nd / 3rd / 4th generation processor, and it is made up of 4 / 8 / 16 / 32 bits.

Name the processor lines of two major manufacturers?High-end: Intel - Pentium (II, III, 4), AMD - Athlon. Low-end: Intel - Celeron, AMD - Duron. 64-bit: Intel - Itanium 2, AMD - Opteron.

What?s the speed and device maximum specs for Firewire?IEEE 1394 (Firewire) supports the maximum of 63 connected devices with speeds up to 400 Mbps. Where?s MBR located on the disk? Main Boot Record is located in sector 0, track 0, head 0, cylinder 0 of the primary active partition.

Where does CPU Enhanced mode originate from?Intel?s 80386 was the first 32-bit processor, and since the company had to backward-support the 8086. All the modern Intel-based processors run in the Enhanced mode, capable of switching between Real mode (just like the real 8086) and Protected mode, which is the current mode of operation.

How many bit combinations are there in a byte?Byte contains 8 combinations of bits.

Have you studied buses? What types?There are three types of buses.Address bus: This is used to carry the Address to the memory to fetch either Instruction or Data.Data bus : This is used to carry the Data from the memory.Control bus : This is used to carry the Control signals like RD/WR, Select etc.

What is the Maximum clock frequency in 8086?5 Mhz is the Maximum clock frequency in 8086.

What is meant by Maskable interrupts?An interrupt that can be turned off by the programmer is known as Maskable interrupt.

What is Non-Maskable interrupts?An interrupt which can be never be turned off (ie. disabled) is known as Non-Maskable interrupt

What are the different functional units in 8086?Bus Interface Unit and Execution unit, are the two different functional units in 8086.

What are the various segment registers in 8086?Code, Data, Stack, Extra Segment registers in 8086.

What does EU do?Execution Unit receives program instruction codes and data from BIU, executes these instructions and store the result in general registers.

Which Stack is used in 8086? k is used in 8086?FIFO (First In First Out) stack is used in 8086.In this type of Stack the first stored information is retrieved first.

What are the flags in 8086?In 8086 Carry flag, Parity flag, Auxiliary carry flag, Zero flag, Overflow flag, Trace flag, Interrupt flag, Direction flag, and Sign flag.

What is SIM and RIM instructions?SIM is Set Interrupt Mask. Used to mask the hardware interrupts.RIM is Read Interrupt Mask. Used to check whether the interrupt is Masked or not.

What is the difference between 8086 and 8088?The BIU in 8088 is 8-bit data bus & 16- bit in 8086.Instruction queue is 4 byte long in 8088and 6 byte in 8086.

Give example for Non-Maskable interrupts?Trap is known as Non-Maskable interrupts, which is used in emergency condition.

Give examples for Micro controller?Z80, Intel MSC51 &96, Motorola are the best examples of Microcontroller.

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INSTRUMENTATION:Objective Type QuestionsInstrumentation System & Devices (IDS)11. A balance beam scale uses which of the following units?a. gramsb .poundsc. ouncesd. kilograms2. Which of the following would be about the height of the average doorway?a. 2 metersb. 2 centimetersc. 2 millimetersd. 2 kilometers3. A series dissipative regulator is an example of a:a. linear regulatorb. switching regulatorc. shunt regulatord. dc-to-dc converter4. Which of the following is a unit of mass in the metric system?a. gramb. milliliterc. centimeterd. pounds5. What device is similar to an RTD but has a negative temperature coefficient?a. Strain gaugeb. Thermistorc. Negative-type RTD

d. Thermocouple6. The resistive change of a strain gaugea. is based on the weight placed upon it, but can be many thousands of ohmsb. is usually no more than 100 omega.c. is based on the gauge factor, but is typically less than an ohmd. has a positive temperature coefficientObjective Type QuestionsInstrumentation System & Devices (IDS)27. The output voltage of a typical thermocouple isa. Less than 100 mVb. Greater than 1 Vc. Thermocouples vary resistance, not voltage.d. None of the above8. The connections to a thermocouplea. Can produce an unwanted thermocouple effect, which must be compensated forb. Produce an extra desirable thermocouple effectc. Must be protected, since high voltages are presentd. Produce an extra desirable thermocouple effect and must be protected, since highvoltages are present9. What is the zero-voltage switch used for?a. To reduce radiation of high frequencies during turn-on of a high current to a loadb. To control low-voltage circuitsc. To provide power to a circuit when power is lostd. For extremely low-voltage applications10. Temperature sensing can be achieved by the use ofa. Thermocouplesb. RTDsc. thermistorsd. All of the above11. The purpose of compensation for a thermocouple isa. to decrease temperature sensitivityb. to increase voltage outputc. to cancel unwanted voltage output of a thermocoupled. used for high-temperature circuits12. The change in value of an analog signal during the conversion process produces what iscalled thea. Quantization errorb. Resolution errorc. Nyquist errord. Sampling errorObjective Type QuestionsInstrumentation System & Devices (IDS)313. Which of the following performance specifications applies to a sample-and-hold circuit?a. Aperture time

b. Aperture droopc. Feedbackd. Acquisition jitter14. RTDs are typically connected with other fixed resistorsa. In a pi configurationb. In a bridge configurationc. And variable resistorsd. And capacitors in a filter-type circuit15. Holding current for an SCR is best described asa. The minimum current required for turn-offb. The current required before an SCR will turn onc. The amount of current required to maintain conductiond. The gate current required maintaining conduction16. What is the moving part of a linear variable differential transformer?a. Primaryb. Secondaryc. Diaphragmd. Core17. What does a Hall Effect sensor sense?a. Temperatureb. Moisturec. Magnetic fieldsd. Pressure18. What causes the piezoelectric effect?a. Heat or dissimilar metalsb. Pressure on a crystalc. Water running on irond. A magnetic fieldObjective Type QuestionsInstrumentation System & Devices (IDS)419. What type of application would use a photovoltaic cell?a. An automobile hornb. A TI 92 calculatorc. A magnetic field detectord. A remote power source20. Which is the seven-segment display?21. A transducer's function is to:a. Transmit electrical energyb. Convert energyc. Produce mechanical energyd. Prevent current flow22. Derived units are obtained from various combinations ofa. Electrical quantitiesb. Fundamental unitsc. Metric prefixes

d. International standards23. Scientific notation is a methoda. of expressing a very large numberb. of expressing a very small numberc. used to make calculations with large and small numbersd. All of the above24. If you drop a 5 when rounding a number, you are using thea. round-to-even ruleb. significant digit rulec. round-off ruled. retained digit ruleObjective Type QuestionsInstrumentation System & Devices (IDS)525. A measure of the repeatability of a measurement of some quantity isa. errorb. precisionc. accuracyd. significant26. Another name for "fundamental units" isa. base unitsb. atomsc. the metric systemd. letter symbols27. When using the terms "accuracy" and "precision" for measurementsa. "precision" implies less measurement error than "accuracy"b. "accuracy" implies less measurement error than "precision"c. "precision" measures the repeatability of a measurementd. both terms mean the same thing28. The difference between scientific and engineering notation isa. powers of ten representationb. single vs. multiple digits before decimal pointc. groupings of multiples of three digitsd. All of the above29. The digits in a measured number that are known to be correct are calleda. accuracy digitsb. significant digitsc. error digitsd. precision digits30. Pico is what relation to micro?a. one-tenthb. one-hundredthc. one-thousandthd. one-millionthObjective Type QuestionsInstrumentation System & Devices (IDS)

631. Four terminal resistors are used for resistance valuesa. Greater than 10 ohmb. Greater than 1 ohmc. Less than 1 ohmd. Of the order of 1M ohm32. The condition for a resistor to have the same value of resistance at medium frequenciesis as with D.C. isa. CR ²=Lb. CR ²=2Lc. CR ²=WLd. CR ²=2WL33. Permeability is the inverse equivalent of which electrical term?a. Voltageb. Currentc. Resistanced. Conductance34. What is the flux density of a magnetic field whose flux is 3000 μWb and cross-sectionalarea is 0.25 m ²?a. 12,000 μ Tb. 83,330 μ Tc. 0 μ Td. More information is needed in order to find flux density.35. How much flux is there in a magnetic field when its flux density is 5000 mu.gifT and itscross-sectional area is 300 mm ²?a. 16.67 m Wbb. 5.0 μ Wbc. 3.0 m Wbd. 1.5 μ Wb36. What are the effects of moving a closed wire loop through a magnetic field?a. A voltage is induced in the wire.b. A current is induced in the wire.c. The polarity across the wire depends on the direction of motion.d. All of the aboveObjective Type QuestionsInstrumentation System & Devices (IDS)737. The Hall Effecta. is a phenomenon with no practical applicationsb. is used in various sensor applicationsc. can develop potentials of thousands of voltsd. is the basis for solar cell operation38. A Hall Effect sensora. exists only in theoryb. is a non-contacting magnetic sensorc. can operate only a few times before failure

d. produces very large voltages39. Which two values are plotted on a B-H curve graph?a. Reluctance and flux densityb. Permeability and reluctancec. Magnetizing force and permeabilityd. Flux density and magnetizing force40. for turbulent flow, the velocity at the center is ____ times the mean velocitya. 1.2b. 2.2c. 2d. 3.333N.B:- Red colors are answers

COMPUTER COMMUNICATION NETWORKS

Multiple Choice Questions (MCQ) of Computer Communication Network

1. If a computer on the network shares resources for others to use, it is called ____a. Serverb. Clientc. MainframeAnswer : a

2. Terminators are used in ______ topology.a. Busb. StarAnswer : a

3. In _____ topology, if a computer’s network cable is broken, whole network goes down.a. Busb. StarAnswer : a

4. For large networks, _______ topology is used.a. Busb. Starc. RingAnswer : b

5. ISO stands fora. International Standard Organizationb. International Student Organizationc. Integrated Services Organization

Answer : a

6. ISO OSI model is used ina. Stand alone PCb. Network environmentAnswer : b

7. Network cable lies on _____ layera. Applicationb. Networkc. Physical

8. ____ layer decides which physical pathway the data should take.a. Applicationb. Networkc. PhysicalAnswer : c

9. ISDN is an example of ______ networka. Circuit switchedb. Packet switchedAnswer : a

10. X.25 is an example of ______ networka. Circuit switchedb. Packet switchedAnswer : b

11. _____________ allows LAN users to share computer programs and data.a. Communication serverb. Print serverc. File serverAnswer : c

12. Print server uses ________ which is a buffer that holds data before it is send to the printer.a. Queueb. Spoolc. NodeAnswer : b

13. A standalone program that has been modified to work on a LAN by including concurrency controls

such as file and record locking is an example of____a. LAN intrinsic softwareb. LAN aware softwarec. Groupwared. LAN ignorant softwareAnswer : a

14. The ______ portion of LAN management software restricts access, records user activities and audit data etc.a. Configuration managementb. Security managementc. Performance managementAnswer : b

15. What is the max cable length of STP?a. 100 ftb. 200 ftc. 100 md. 200 mAnswer : d

16. What is the max data capacity of STP?a. 10 mbpsb. 100 mbpsc. 1000 mbpsd. 10000 mbpsAnswer : b

17. Which connector STP uses?a. BNCb. RJ-11c. RJ-45d. RJ-69Answer : c

18. What is the central device in star topology?a. STP serverb. Hub/switchc. PDCd. RouterAnswer : b

19. What is max data capacity for optical fiber cable?a. 10 mbpsb. 100 mbpsc. 1000 mbpsd. 10000 mbpsAnswer : c

20. Which of the following architecture uses CSMA/CD access method?a. ARCnetb. EthernetAnswer : b

DIGITAL ELECTRONICS:

1. The voltage levels for a negative logic system

(a) must necessarily be negative

(b) could be negative or positive

(c) must necessarily be positive

(d) must necessarily be either zero or —5 V

2. The output Qn of a J-K flip-flop is zero. It changes to 1 when a clock pulse is applied. The inputs Jn and Kn are respectively

(a) 1 and X

(b) 0 and X

(c) X and 0

(d) X and 1

3. The larger the RAM of a computer, the faster is its speed, since it eliminates

(a) need for ROM

(b) need for external memory

(c) frequency disk I/O s

(d) need for a data-wide path

4. DB, DW and DD directives are used to place data in particular location or to simply allocate space without preassigning anything to space. The DW and DD directories are used to generate

(a) offsets

(b) full address of variables

(c) full address of labels

(d)offsets of full address of labels and variables

5. The number of bits needed to address 4K memory is

(a)6

(b) 8

(c)12

(d) 16

6. The ESC instruction of 8086 may have two formats. In one of the formats, no memory operand is used. Under this format, the number of external op-codes (for the co-processor) which can be specified is?

(a) 64

(b) 128

(c) 256

(d) 512

7. The TRAP is one of the interrupts available its INTEL 8085. Which one of the following statements is true of TRAP?

(a) It is level triggered

(b) It is negative edge triggered

(c) It is positive edge triggered

(d) It is both positive edge triggered and level triggered

8. In a 16-bit microprocessor, words are stored in two consecutive memory locations. The entire word can be read in one operation provided the first

(a) word is even

(b) word is odd

(c) memory location is odd

(d) memory address is even

9. A 3 x 8 decoder with two enable inputs is to be used to address 8 blocks of memory. What will be the size of each memory block when addressed from a sixteen bit bus with two MSBs used to enable the decoder

(a) 2K

(b) 4K

(c)16K

(d) 64K

The following . items consist of two statements, one labeled as ‘Assertion A ‘ and the other labeled the ‘Reason R’. You are to examine these two statements carefully and decide if the Assertion A and the Reason R are individually true and if so, whether the Reason is a correct explanation of the Assertion. Select your answers to these items using the codes given below and mark your answer sheet accordingly:

Codes:

(a) Both A and R are true and R is the correct explanation of A.

(b)Both A and Rare true but R is NOT a correct explanation of A.

(c) A is true but R is false

(d)A is false but R is true

10. Assertion (A): TTL and CMOS cannot be normally used together.

Reason (R) : .TTL operates on a (±5 0.25) V regulated supply voltage and some mA, while the CMOS operates on unregulated supply voltage of +3 to +15 and some microA.

11. Assertion (A): Machine language program is written in hexadecimal.

Reason (R) : Microprocessor can understand hexadecimal number system.

12.A JK flip-flop has its J input connected to logic level 1 and its K input to the Q

output. A clock pulse is fed to its clock input. The flip-flop will now

(a) change its state at each clock pulse

(b) go to state 1 and stay there

(c) go to state 0 and stay there

(d) retain its previous state

13.A decade counter requires

(a) 10 flip-flops

(b) 4 flip-flops

(c) 3 flip-flops

(d) 2 flip-flops.

14 The decimal value for the BCD coded number 00010010 is

(a) 6

(b) 10

(c)12

(d)18.

15. The Boolean expression (A+C÷D) (B+D+C)

may be simplified as

(a) AB + CB

(b)AB+C+÷D

(c) A+BC+D

(d) A+B+CD.

16. An adder takes……. Input/s and produces………. Output/s

(a) one, two

(b) two, two

(c) three, two

(d) two, three.

17.1 Increasing the precision of the REAL data type requires using at least one additional bit in

(a) the mantissa

(b) the exponent

(c) both the mantissa and the exponent

(d) none of the above.

18. Let * be the binary operation on rational numbers given

a*b=a+b+2ab. Which of following are true?

I. * is commutative

II. There is a rational number that is a*identity

III. Every rational number. has as a* inverse.

(a) I only

(b) II only

(c) I and II

(d) I,II and III

19..How many 1 are present in the binary

representation of 15 x 256 + 5 x 16 + 3?

(a) 8

(b) 9

(c) 10

(d)11

20. Which of the following combinations of gates does not allow the implementation

of an arbitrary Boolean function?

(a) OR gates and inverters only

(b) NAND gates only

(c) OR gates and exclusive – OR gates only

(d) OR gates and NAND gates.

21.Which logic circuit is the fastest?

(a) TTL

(b) DTL

(c) RTL

(d) All have same speed.

22.A half adder has

(a) 2 inputs and 2 outputs

(b) 2 inputs and 3 outputs

(c) 3 inputs and 3 outputs

(d) None of the above.

23. The main advantage of flip-flops over transistor circuit is

(a) immunity from noise

(b) low heating

(c) low propagation delay time

(d) high propagation.

24. The Integrated injection Logic has higher density of integration than TT’L because it

(a) does not require transistors with high current gain and hence they have smaller geometry

(b) uses bipolar transistor

(c) does not require isolation diffusion

(d) uses dynamic logic instead of static logic.

25.In a positive edge triggered JK flip-flop, a

low J and a low K produce the……. state A

high J and a high K mean that the output

will …….on the rising edge of the clock

(a) active…. race

(b) inactive ……dead

(c) inactive …..toggle

(d) active …..constant

26.How many bits does one need to encode all twenty-six letters, ten symbols, and ten

numerals?

(a) 5

(b) 6

(c) 7

(d) 46

27. Consider the representation of six-bit numbers by two’s complement, one’s

complement, or by sign = and magnitude.In which representation is there overflow

from the addition of the integers 1000 and 011000 ?

(a) Two’s complement only

(b) Sign and magnitude and one’s complement only

(c) Two’s complement and one’s complement only

(d) All three representations.

28. Which of the following sets represents a universal logic family?

(a)NAND

(b)XOR

(c)NAD

(d) None of the above.

29. The maximum propagation value in case of 7400 NAND gates is

(a) 1 second

(b) 20 milli seconds

(c) less than 20 nano seconds

(d) less than 20 pico seconds.

30 . The total number of Boolean functions which can be realized with your variables

Is ?

(a) 4

(b)16

(c) 256

(d) 65,536

Answers :

1b 13d 25c2a 14c 26b3c 15b 27d4d 16c 28a5c 17a 29c6b 18c 30b

7d 19a

8d 20d

9c 21a

10b 22a

11d 23c

12a 24b

DIGITAL ELECTRONICS;

1.The number of digits in octal system isa.8b.7c.10d. none

2..The number of digits in Hexadecimal system isa.15b.17c.16d. 8

3.The number of bits in a nibble isa.16b.5c.4d.8

4.The digit F in Hexadecimal system is equivalent to —— in decimal systema.16b.15c.17d. 8

5.Which of the following binary numbers is equivalent to decimal 10a.1000b.1100c.1010d.1001

6.The number FF in Hexadecimal system is equivalent to —— in decimal systema.256b.255c.240d.239

7.IC s area. analogb. digitalc. both analog and digitald. mostly analog

8.The rate of change of digital signals between High and Low Level isa. very fastb. fastc. slowd. very slow

9. Digital circuits mostly usea. Diodesb. Bipolar transistorsc. Diode and Bipolar transistorsd. Bipolar transistors and FETs

10.Logic pulsera. generates short duration pulsesb. generate long duration pulsesc. generates long and short durationd. none of above

11.What is the output state of an OR gate if the inputs are 0 and 1?a.0b.1c.3d.2

12.What is the output state of an AND gate if the inputs are 0 and 1?a.0b.1c.3d.2

13.A NOT gate has…a. Two inputs and one outputb. One input and one output

c. One input and two outputsd. none of above

14.An OR gate has…a. Two inputs and one outputb. One input and one outputc. One input and two outputsd. none of above

15.The output of a logic gate can be one of two _____?a. Inputsb. Gatesc.Statesd. none

16.Logic states can only be ___ or 0.a. 3b. 2c.1d.0

17.The output of a ____ gate is only 1 when all of its inputs are 1a. NORb. XORc. ANDd. NOT

18.A NAND gate is equivalent to an AND gate plus a …. gate put together.a. NORb. NOTc. XORd. none

19.Half adder circuit is ______?a. Half of an AND gateb. A circuit to add two bits togetherc. Half of a NAND gated. none of above

20. Numbers are stored and transmitted inside a computer ina. binary formb. ASCII code formc. decimal formd. alphanumeric form

21.The decimal number 127 may be represented by

a. 1111 1111Bb. 1000 0000Bc. EEHd. 0111 1111

22.. A byte corresponds toa. 4 bitsb. 8 bitsc. 16 bitsd. 32 bits

23.A gigabyte representsa.1 billion bytesb. 1000 kilobytesc. 230 bytesd. 1024 bytes

24. A megabyte representsa. 1 million bytesb. 1000 kilobytesc. 220 bytesd. 1024 bytes

25.. A Kb corresponds toa. 1024 bitsb. 1000 bytesc.210 bytesd. 210 bits

1.a2.c3.c4.a5.c6.a7.c8.a9.c10.b11.b12.a13.c14.a15.a

16.c17.c18.a19.b20.a21.c22.b23.a24.b25.b